Automatic controls for airplane take-off and landing modes

Abstract

A take-off and landing control device for automatic retraction of flaps upon stowing landing gear and upon attaining a predetermined airspeed and of indicating distance from brake release during take-off, and for an automatic decelerating approach with flaps extending as a function of distance from touchdown with automatic throttle cutback and automatic stabilizer trim in response to flap location maintaining an essentially constant angle of attack.

What is claimed is: 
     
       1. A device for controlling a flight pattern of an aircraft during take-off comprising: means for automatically retracting flaps in response to a sensed predetermined airspeed after stowing landing gear, said means comprising: means for comparing a voltage proportional to a preselected airspeed with a voltage proportional to airspeed from a central air data computer to impart a command voltage, and means for retracting the flaps upon the command voltage being received by the servo-amplifier, wherein the means for retracting the flaps in response to command voltage being received by the servo-amplifier comprises: a transfer valve controlled by the servo-amplifier, and a hydraulic motor driven by hydraulic fluid from the transfer valve; and means for determining and for indicating airplane position over a predetermined ground location at which point engine thrust is cut back to reduce the noise of climb-out. 
     
     
       2. A device for controlling a flight pattern of an aircraft during take-off comprising: means for automatically retracting flaps in response to a sensed predetermined airspeed after stowing landing gear; and means for determining and for indicating airplane position over a predetermined ground location at which point engine thrust is cut back to reduce the noise of climb-out wherein the means for determining and indicating airplane position comprises: means by which distance from point of departure is obtained from an Inertial Navigation System. 
     
     
       3. A device for controlling a flight pattern of an aircraft during take-off comprising: means for automatically retracting flaps in response to a sensed predetermined airspeed after stowing landing gear; and means for determining and for indicating airplane position over a predetermined ground location at which point engine thrust is cut back to reduce the noise of climb-out wherein the means for determining and indicating airplane position comprises: means by which distance from an airport is determined by use of onboard Distance Measuring Equipment receivers. 
     
     
       4. A device for controlling an airplane flight pattern during take-off comprising: means for imparting a landing gear up signal; means for comparing a voltage proportional to airspeed from a central air data computer with a voltage proportional to a preselected airspeed to impart a command voltage; a combination of a servo amplifier, a transfer valve, and a hydraulic motor activated to retract flaps upon receiving the command voltage and the gear up signal; means for twice integrating a proportional voltage from an autothrottle accelerometer, means for comparing the integrated proportional voltage with a voltage proportional to a preselected distance from a take-off starting point to generate a command voltage; an amplifier for the generated command voltage and a signaling device to notify an operator that the preselected position has been reached at which engines may be cut back. 
     
     
       5. An arrangement for automatically controlling a decelerating approach of an airplane comprising: means for generating a continuing flap command signal, over a preselected glide-slope portion of an approach, as a function of distance from touchdown; means for translating the flap command signal into a power source to extend the flaps over the selected interval; means for sensing flap position; and means for automatically reducing thrust to a preselected level and for automatically trimming a stabilizer in response to flap position to maintain an essentially constant angle of attack. 
     
     
       6. An arrangement as in claim 5 wherein the means for generating a flap command comprises: means for continually determining distance from touchdown, and a function generator for converting the determined distance into the flap command signal. 
     
     
       7. An arrangement as in claim 6 wherein distance is measured as horizontal distance to touchdown. 
     
     
       8. An arrangement as in claim 6 wherein distance is measured as vertical distance to touchdown. 
     
     
       9. An arrangement as in claim 5 wherein the means for automatically reducing thrust comprises: a function generator to convert sensed flap position into a speed differential signal; a comparator to compare the speed differential signal with a preselected final speed signal to impart an auto-throttle command signal to the engines. 
     
     
       10. An arrangement as in claim 9 wherein the means for trimming the stabilizer comprises: a function generator to continually convert the sensed flap position into a trim signal; a multiplier to multiply the trim signal with a signal indicating a bias modified stabilizer position at the start of the preselected portion of the approach to give a trim command signal; and a trim motor acted on by the trim command to actuate the stabilizers. 
     
     
       11. An arrangement as in claim 10 further comprising: means for imparting a thrust moment compensation signal from the thrust control auto-throttle to modify the trim command signal. 
     
     
       12. An arrangement for automatically controlling a decelerating approach of an airplane comprising: means for continually determining distance from touchdown, means for converting a determined distance into a flap command signal, means for translating the flap command signal into a power source to extend the flaps, means for sensing flap position, means for converting sensed flap position into a speed differential signal, means for adding the speed differential signal to the preselected final speed signal to obtain a speed command signal; means for comparing the speed command signal with a signal proportional to airspeed to generate a speed reducing signal; an auto-throttle to transmit the signal to reduce the thrust of the engines, means for converting sensed flap position into a trim differential signal; means for generating a signal based on stabilizer position at the start of the decelerating approach as modified by a bias signal; means for summing the modified stabilizer initial position signal with the trim differential signal to obtain an automatic trim command signal; and means for utilizing the command signal to actuate the stabilizer. 
     
     
       13. A method of controlling a flight pattern of an aircraft during take-off and approach modes, the steps comprising: extending the flaps for take-off; entering a predetermined speed in a control panel; engaging an automatic flap mode to compare actual speed with the predetermined speed to retract the flaps with landing gear stowed and predetermined speed reached; arming an automatic signalling device to indicate reaching a preselected distance from the start of the take-off; cutting back on the throttle, during climbout, upon receiving the distance signal; selecting a distance interval from touchdown for a decelerating approach during the approach mode; arming the automatic flap control to extend the flaps in response to distance from touchdown; entering a predetermined lower limit of speed for the end of the decelerating approach; arming the automatic decelerating throttle controls to reduce thrust in response to sensed flap position; entering a bias to stabilizer position at point of initial deceleration, and arming an automatic trim control system to respond to sensed flap position in combination with bias modified initial stabilizer position.